The goals of this project include the analysis of molecular genetic alterations in the human uterine pathology, specifically endometrial carcinoma and endometriosis. Additionally, studies are underway to determine the genetic basis of dual primary breast-ovarian carcinoma cases and a possible genetic basis of human gynecologic cancers associated with prenatal exposure to diethylstilbestrol. These studies are being carried out with DNA obtained from archival formalin-fixed, paraffin-embedded tissue blocks, fresh-frozen biopsy samples, and established cell lines in culture. Through the analysis of endometrial hyperplasia and carcinoma samples, we have determined that activating point mutation of codon 12 of the Ki-ras oncogene is an early event in a subset of endometrial carcinomas, whereas mutation of the p53 tumor suppressor gene appears to be a later event in endometrial tumorigenesis. A significant number of endometrial carcinomas exhibit allelic loss and/or mutation of the DCC tumor suppressor gene. Using a cultured human neuronal cell model, the DCC gene was additionally shown to be involved in cellular differentiation. Aberrant expression of transforming growth factor-alpha as well as a number of additional cytokines (e.g., tumor necrosis factor-beta and interleukin- 6) was shown to be a common feature of endometrial carcinoma and endometriosis, compared to normal endometrium; a clear role for TGF-alpha in autocrine growth regulation of endometrial carcinoma cells was demonstrated. Significant progress has also been made in a complete allelotyping analysis of human endometrial carcinoma, and in a partial allelotyping analysis of dual primary breast-ovarian carcinoma, in order to ascertain additional tumor suppressor genes that may be relevant to these cancer types. Finally, studies were initiated to determine a possible molecular genetic basis for diethylstilbestrol-associated human and rodent gynecologic neoplasms; the initial target genes include ras and p53. Future work will be designed to contribute to a complete molecular genetic description of the above described tumor types.